Flowering species from the tropical north, Kimberley region, from desert to rainforest, that all love more CO2.
Mortensen grew roses (Rosa ‘Mercedes’) in growth chambers with atmospheric CO2 maintained at 330 ppm and 1,000 ppm. The plants increased their dry weight by 21% thanks to the extra CO2. Mortensen also grew two varieties of African violets in these chambers, and their dry weights increased by 40.8 and 58.3% given elevated CO2. The violets increased the number of plants producing flowers, the elevated CO2 decreased the number of days to flowering by a full week, and the number of flowers and flowerbuds more than doubled in the chambers with elevated CO2. Maybe you prefer mums instead of orchids, roses, or violets? You guessed it – Mortensen grew two variety of mums as well, and the elevated CO2 caused them to increase their dry weight by 27.8% and 67.1%.
We could go on and on – Mortensen grew lettuce, cucumbers, tomato, moss, ivy, and other flowers, and the CO2 effect on dry weight ranged from 21.4% for the roses to 74.0% for the lettuce. More reasons for happiness, more reasons to give flowers, and more reasons to welcome higher levels of CO2.